Castiel
by Nomino
Summary: By the time they found out how to cure him, it was already too late. Dean was long gone, the mark of cain completely taking over his humanity and corrupting the last visage of grace Castiel left when he raised the human from perdition. Relationship: Dean Winchester/Castiel Tags: Demon Dean, Angel Castiel, Human Castiel


By the time they found out how to cure him, it was already too late./

Dean was long gone, the mark of Cain completely taking over his humanity and corrupting the last visage of grace Castiel left when he raised the human from perdition.

They locked him up in the dungeon, Hannah helping them put on better wards, but it can't hold the demon much longer. They needed to act, and they needed to act fast.

The cure, while it would still work - still bring Dean back - it costs too much for it to take effect. It costs the grace of an angel, but not just any angel. It doesn't work like that. Not when dean's too far from the surface, not when the human is trap inside his own hell, it has to be the grace of an angel who is in love; unconditionally and eternally in love with humanity.

With the human that needed saving.

Without batting an eye, without hinting and without acknowledging it, Castiel - the angel of the Lord, a seraph in his time with tattered wings from saving a human soul from hell and eyes still as bright as the day he first laid in his vessel and so human, so in love - offered his self.

No one questioned it, it wasn't even a surprise when he took his blade and gave it to Sam.

Sam never doubted but he hesitated, yes. Not because he thinks it'll fail, that it might not work, that maybe Castiel doesn't fit the criteria, but because he fits the criteria too well.

"Don't tell him." He told Sam, as he took the vial of grace from the human... _the other human_. "It is best, that he does not know." and Sam doesn't know either if Castiel is talking about him giving up his grace or him being in love with his brother.

"Cas-"

"Sammuel." He cuts mid sentence, _"Thank you."_

"Hello Dean." He speaks gently, sadness and fondness pooling his eyes.

"Who do I owe the pleasure?" the demon slurs, "a _human_?"

There was a pause, " _Yes._ " he answered to which the demon laughed.

It was the same process, as curing a demon the only difference is the materials, the necessities, the incantations and _the everything._

"I see," Castiel's been going at it for hours, but the demon is persistent. "I see the filth that is your existence. The blood of your brother's in your hand."

Another stab of grace and the demon huffs. He's running out, yet the demon feels just as strong as before.

"There's blood everywhere" the demon continues, taunting him, laughing, laughing and laughing.

"So you are Castiel." Two more syringe left and the demon's weakening. Castiel never answers.

"I see you in his mind, Castiel. Looks like this is working, yes?" the demon's voice has gone soft now, a little timbre of Dean's gruffness can be heard somewhere in his lines, "I see you through his eyes, you know?" The demon asks, "Do you want to know _how_ he sees you?" this caught Castiel's attention, but he doesn't answer.

It is still not Dean, so he doesn't answer.

 _"Beautiful."_

The demon passed out. One more, ione final blowi and it'll end. They'll have Dean back, they'll fix what's broken together like always, like how Dean said they should do back when he was with Crowley.

"Cas..." his thoughts halts, 'Cas? Could it be Dean? Has he finally...' "He loves you, you know?"

 **Stop.** "Stop!"

"Oh, Castiel." the Demon sing songs weakly, "Why did you taint your existence with this kind of love?"

And that was the last straw, that broke Castiel. How dare this demon, uses Dean's voice to classify his feelings for Dean like it is so trivial?

Castiel grabbed the syringe, brokenness evident in his face as he stabbed the demon the final drop of his grace.

And it was as if it was Dean that bared his neck.

He was about to press it when he felt something draining his chest, but it doesn't matter now, not yet.

He empties the syringe, and watch as the eyes below him fades with darkness, yes, he can see it slowly the way green eats the black away, so beautiful. It has been long since he last saw such beautiful color. Yes, he got Dean back.

Castiel smiled, genuinely. It was a tired smile but a smile nonetheless and he hopes Dean doesn't see it as a grimace, he's just tired is all.

He can hear Dean now, though he's slipping to unconsciousness fast, he can hear Dean's voice clearly even when it is laced with grief and sorrow, why is dean grieving?

"Cas... Cas... please..."

"No no no no I'm sorry, I'm sorry."

"Sam! Sammy!"

"Help me please! Sammy! Cas is..."

"Come on buddy, don't close your eyes, come on."

"Hannah, Hannah I need you. It's Castiel... Please anyone!"

"Castiel, I need you. I need you, don't... Please don't..."

"I..."

Oh.

Thank Father. Dean's back.

"you... I love you."


End file.
